The present invention relates to a motorized road-going vehicle for making trenches in the ground, allowing the subsequent laying of elongate objects such as, for example, optical and/or electric cables, pipe lines and/or ducts for fluids, etc.
In general, such a trench in the ground, which may be the pavement or the sidestrip of a road or the like, is made using a digging device with a trenching wheel carried by a special-purpose motorized vehicle which is very often outsized in terms of its width. As the trenching wheel rotates and the vehicle moves forward, a trench is obtained in the ground to the desired depth. In addition, in order to reduce the time that the work takes, because of the disruption it causes, another vehicle is used to suck up and collect the spoil produced during the digging of the trench as it exits the cutting face of the trenching wheel. This other vehicle may be coupled to the first and carry an appropriate device for sucking and collecting the spoil so that once this mechanised unit consisting of the two separate vehicles moving in convoy has passed, the pavement is in a clean state and the cables are ready to be laid in the trench thus produced.
Although the mechanised unit formed by these two motorized vehicles, with which the digging and sucking-up devices are respectively associated, yields good results as far as the trench obtained is concerned, it entails significant and expensive logistic planning and takes up a considerable amount of space on the road network. In addition, while such a mechanised unit, which may be as much as 25 to 30 meters long, is relatively operational on heavily used routes of the interstate, main road or major arteries through a town type, the same cannot be said when it comes to laying cables along secondary routes, where it is then necessary to completely interrupt the flow of traffic or at best set up alternating traffic flow to allow the mechanised unit to operate in complete safety. Further, in certain instances, the mechanised unit may even be unable to run along roads which are too narrow.
The object of the present invention is to overcome these drawbacks.
To this end, the motorized road-going vehicle for making trenches in the ground, of the type comprising, on its chassis, a device for digging trenches using a trenching wheel, which can be moved with respect to said chassis at least transversely to the longitudinal axis of said chassis and orthogonally with respect to the latter so as to position the trenching wheel in the ground, is notable, according to the invention, in that it additionally comprises, on its chassis, a device for sucking up and collecting the spoil produced while the trench is being dug, in association with the exit of the cutting face of the ditch produced by said trenching wheel, and in that said trenching wheel is carried by a frame which is mounted so that it can pivot, about a pivot pin orthogonal to the chassis, so that it occupies either a work position projecting with respect to said chassis so as to make said trench, or a transport position brought onto said chassis.
Thus, by virtue of the invention, one single same vehicle carries out the functions of digging the trench and sucking up and collecting the spoil, which makes it possible, under working conditions, to considerably reduce the disruption caused when carrying out works on the road network and also to reduce the logistics involved and therefore the cost of carrying it out. Further, in the transport condition, the vehicle can travel easily and legally because the frame carrying the trenching wheel falls inside the chassis. Thus, the vehicle can be used on the secondary road network. In addition, the self-contained nature of the vehicle according to the invention gives it great flexibility of use allowing it to make trenches at various points during the same day without needing excessive logistic planning.
In order to ensure good distribution of load across said vehicle, said sucking-up and collecting device is arranged at the central part of said chassis and said digging device is arranged at the rear part of the chassis. Advantageously, by the projecting working position of the trenching wheel with respect to the rear of the chassis, that is to say that it is overhanging, imposed by the pivot pin so that the trenching wheel can be switched from one position to the other, a spoil suction duct starting from said sucking-up and collecting device can then be led, at the exit of said cutting face, between the rear of the chassis and the trenching wheel.
Furthermore, said digging device is provided with an actuating member connecting said pivot pin to said frame of the trenching wheel so as to allow it to move from the work position to the transport position and vice versa. In a preferred embodiment, said actuating member is a rotary ram which rotates between 90xc2x0 and 180xc2x0 between the work position and the transport position.
In general, the digging device comprises a post mounted so that it can slide on transverse sideways associated with said chassis, and a carriage carrying said frame and able to slide vertically along said post.
Advantageously, provided between said carriage and the pivot pin is a connecting mechanism making it possible, under the action of a control member, to offset the frame of the trenching wheel transversely beyond a position in which said post is in abutment against the transverse ends of its slideways. For example, said connecting mechanism is of the deformable parallelogram type articulated, about pins orthogonal to the plane of said chassis and parallel to the pivot pin, to said carriage and to said pivot pin, an operating ram shifting the arms of the parallelogram mechanism.
In a preferred embodiment, said sucking-up and collecting device comprises:
equipment for generating a depression, arranged on said chassis;
a collecting vessel for the spoil produced, arranged on said chassis;
a casing associated with the frame of said trenching wheel and enveloping its exterior part located outside the trench, said casing coming into contact with the ground to form, with said exterior part of the wheel, an internal space; and
a duct connecting the outlet of said equipment to said casing so as to suck the spoil generated toward said vessel by pulling a depression in said internal space, using said equipment.
In addition, said sucking-up and collecting device can also comprise an auxiliary duct connected to one side of said casing and arranged, on the other side, to the rear of said wheel, in the bottom of the trench and/or on its lateral edges so as to suck up remaining spoil.
Advantageously, said depression equipment is a turbine and said spoil vessel is mounted so that it can tip on said chassis.